Machine for the manufacture or treatment of a material web

ABSTRACT

A machine for the manufacture or treatment of a material web, in particular of a paper or cardboard web, including a rope guide for the threading of a marginal web strip. The rope guide has two endless ropes which can be brought together to form a rope nip and whose run course can be correspondingly changed for the positioning of the rope nip in a threading position within a plane extending in the machine running direction and perpendicular to the material web.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a machine for the manufacture or treatment of a material web, in particular of a paper or cardboard web, having a rope guide for the threading of a marginal web strip which includes two endless ropes which can be brought together to form a rope nip.

[0003] 2. Description of the Related Art

[0004] A prior art paper making machine is described, for example, in DE-C-40 34 661. The procedure is normally as follows, for example, for the threading of the web to be dried into the dryer section: the web formed and mechanically dewatered in the start part (sieve section and press section) of the paper making machine temporarily runs only up to the end of the press section during the start-up phase and from there into a pulper, with a narrow marginal strip being separated from the web and transferred into the dryer section. As soon as the tip of this marginal strip has reached the end of the dryer section, the marginal strip is gradually broadened until it has reached the full web width.

[0005] For the threading of the material web, for example, into the dryer section or also into any desired other section of the paper making machine, in particular a rope guide can now be used whose two ropes converge or run together to form a so-called rope nip such that the tip of the marginal strip can be gripped and transported on. A deflection device can be provided in front of the rope nip in the web running direction and the tip of the arriving marginal strip is laterally deflected into the rope nip out of the region of the web width thereby.

[0006] The ropes of a respective rope guide are usually guided transversely to the machine running direction in order to prevent interference or a collision of these ropes with other moving parts, for example, of a scanning device or the like. In this respect, however, a crossing over of the ropes now frequently occurs, which involves heavy wear of the ropes in view of the friction between the ropes and the additional deflection at right angles around rope pulleys.

[0007] What is needed in the art is a machine where the crossing over of the ropes is reduced, thereby reducing the heavy wear of the ropes and also reducing additional deflection at right angles around rope pulleys.

SUMMARY OF THE INVENTION

[0008] The present invention provides an adjustable run course for a rope guide.

[0009] The present invention comprises, in one form thereof, a machine for the manufacture or treatment of a material web, in particular of a paper or cardboard web, including a rope guide for threading a marginal web strip, which includes two endless ropes which can be brought together to form a rope nip, and whose run course can be correspondingly changed for the positioning of the rope nip in a threading position within a plane extending in the machine running direction and perpendicular to the material web.

[0010] It is now possible on the basis of this design to transpose the ropes generally in the machine running direction such that the rope nip is generated at an optimum position for the threading or is transposed into such an optimum threading position. The ropes are subsequently retracted again in order to allow trouble-free operation or trouble-free handling of a device provided in each case in the region of the threading point, for example a scanning device or the like. If, for example, a web scanning device is provided in this region, in particular a full web scan is also again possible after a respective retraction of the ropes.

[0011] In an expedient practical embodiment of the machine of the present invention, the position of the rope nip can be changed within the plane extending in the machine running direction and perpendicular to the material web. The two ropes of the rope guide are preferably guided independently of the position of the rope nip, in each case exclusively in a plane extending in the machine running direction and perpendicular to the material web. The position of the rope nip can advantageously generally be changed in the machine running direction.

[0012] In accordance with a preferred practical embodiment of the apparatus of the present invention, the two ropes of the rope guide can be guided for the positioning of the rope nip in a threading position into the region of a device, in particular of a web scanning device, and can be retracted to release the device.

[0013] In an expedient practical embodiment, the two ropes of the rope guide can be guided for the positioning of the rope nip in a threading position through the frame of a web scanning device and can be retracted again for the release of the web scanning plane. The rope nip is advantageously adjustable between a threading position in which the two ropes of the rope guide are guided through the frame of a web scanning device and a retracted position in which the web scanning device is released again.

[0014] The rope nip grasping the tip of the marginal web strip can therefore be moved into a threading position, for example through the frame of a scanning device, said threading position being suitable to receive the tip of the marginal strip coming from a preceding machine element such as a press roll or a dryer cylinder. In this respect, the marginal strip can be transported to the relevant transfer point by, for example, an air tray or a conveyor belt.

[0015] A further advantageous embodiment of the embodiment of the present invention is characterized in that the rope guide includes a guide section disposed in front of a web scanning device in the machine running direction and a guide section disposed after the web scanning device in the web running direction; in that the two ropes of the rope guide are guided mutually separated between these two guide sections on mutually opposite sides of the web scanning device; and in that a rope nip is formed at the start of the rear guide section and can be adjusted into a takeover position to take over the material web tip from the front guide section through the frame of the web scanning device and back into a retracted position disposed behind the web scanning device to transfer the material web into the rear guide section.

[0016] The two ropes can be guided over two sheaves, which can be correspondingly positioned via an adjustment device, to form the rope nip.

[0017] The rope guide can be provided, for example, for the threading of a marginal web strip into the dryer section. Generally, however, the rope guide can also be provided for the threading of a marginal web strip into a different machine element.

[0018] An advantage of the present invention is crossing over of the ropes is reduced.

[0019] Another advantage of the present invention is wear of the ropes is reduced.

[0020] A further advantage of the present invention is the reduction of additional deflection at right angles around the rope pulleys.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:

[0022]FIG. 1 is a schematic side view of a paper making machine according to an embodiment of the present invention including a rope guide for threading a marginal web strip into the dryer section;

[0023]FIG. 2 is a schematic side view of the rope guide of FIG. 1;

[0024]FIG. 3 is a schematic side view of another embodiment of the rope guide;

[0025]FIG. 4 is a schematic plan view of an adjustment device according to an embodiment of the present invention; and

[0026]FIG. 5 is a schematic side view of the adjustment device of FIG. 4.

[0027] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate one preferred embodiment of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.

DETAILED DESCRIPTION OF THE INVENTION

[0028] Referring now to the drawings, and more particularly to FIG. 1, there is shown a machine 10, in a schematic side view illustration, for the manufacture or treatment of a material web, which can be in particular a paper web or a cardboard web. Press 12 of the press section and the first two dryer cylinders 14 of the dryer section 15 of a paper making machine can be seen in FIG. 1. Rope guide 16 is provided which in the present case serves, for example, for the threading of a marginal web strip 58 into dryer section 15. Rope guide 16 is also shown again in FIG. 2 in a simplified schematic side view illustration.

[0029] As can be seen from FIGS. 1 and 2, rope guide 16 includes two endless ropes 18, 20 which are brought together in the region of two sheaves 22, 24 to form a rope nip 26. In this respect, the run course of these two endless ropes 18, 20 can be correspondingly changed by way of adjustment device 28 for the positioning of rope nip 26 in a threading position E within a plane extending in the machine running direction L and perpendicular to the material web.

[0030] In the present case, sheave assembly 22, 24 is correspondingly transposed by adjustment device 28 with the spacing between sheaves 22, 24 remaining the same. Rope nip 26 is therefore maintained during a respective transposition of sheave assembly 22, 24. The position of rope nip 26 can thus be changed within the plane extending in the machine running direction L and perpendicular to the material web. In this respect, two ropes 18, 20 of rope guide 16 are each guided independently of the respective position of rope nip 26 only in a plane extending in the machine running direction L and perpendicular to the material web. The position of rope nip 26 can generally be changed in the machine running direction L.

[0031] In the present embodiment (FIGS. 1 and 2), two ropes 18, 20 of rope guide 16 are guided through frame 30 of web scanning device 32 for the positioning of rope nip 26 in threading position E and subsequently retracted for the release of web scanning device 32. Rope nip 26 can thus be adjusted by way of adjustment device 28 between threading position E in which two ropes 18, 20 of rope guide 16 are guided through frame 30 of web scanning device 32 and a retracted position Z in which web scanning device 32 is again released. The sheaves adopting their retracted position Z are designated with 22′ and 24′ respectively in FIGS. 1-3.

[0032] As can be seen by way of FIGS. 1 and 2, the grasped marginal web strip is guided by way of rope guide 16 including two ropes 18, 20 over deflection roll 34 into the dryer section 15 whose first two dryer cylinders 14 can be seen in FIG. 1.

[0033]FIG. 3 shows another embodiment of rope guide 16 in a schematic side view illustration. In this case, rope guide 16 includes guide section 36 disposed in front of web scanning device 30 in the machine running direction L and guide section 38 disposed after web scanning device 30 in the machine running direction L. Two ropes 18, 20 of rope guide 16 are guided mutually separated between these two guide sections 36, 38 on mutually opposite sides of web scanning device 32.

[0034] Rope nip 26 is formed at the start of rear guide section 38. This rope nip 26 is in the present case adjustable into a takeover position E for the takeover of the material web tip 56 from front guide section 36 through frame 30 of web scanning device 32 and back into a retracted position Z disposed after web scanning device 32 for the transfer of the material web into rear guide section 38.

[0035] In this respect, two ropes 18, 20 can be again guided over two sheaves 22, 24, which can be correspondingly positioned via an adjustment device 28 (see in particular also FIGS. 1, 4 and 5) to form rope nip 26.

[0036] An exemplary embodiment of adjustment device 28 is shown in FIGS. 4 and 5. As can be seen from FIGS. 4 and 5, adjustment device 28 includes sheave assembly 40, including two sheaves 22, 24, which can be moved along guide rail 44 by way of piston-in-cylinder unit 42. For this purpose, runner 46 guided at rail 44 is associated with sheave unit 40. As can be seen in particular with reference to FIG. 4, T-arm arrangement 48 is provided in the region of the sheave assembly 40. Piston-in-cylinder unit 42 engages at lug 50 connected to sheave assembly 40. The resulting stroke for sheave assembly 40 is given by h in FIG. 5. In FIG. 5, nip guard 52 provided in the region of sheave assembly 40 can moreover be seen. At least one proximity switch 54 or the like can, for example, be provided to limit the stroke movement of sheave assembly 40.

[0037] While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. 

What is claimed is:
 1. A machine for the manufacture or treatment of a material web, comprising a rope guide including two endless ropes forming a rope nip therebetween, said rope guide being configured for threading a marginal web strip, said rope guide having a run course, said run course being changeable for positioning said rope nip in a threading position within a plane extending in a machine running direction and perpendicular to the material web.
 2. The machine of claim 1, wherein a position of said rope nip is changeable within said plane extending in said machine running direction and perpendicular to the material web.
 3. The machine of claim 1, wherein said two ropes are guided independently of a position of said rope nip, both said ropes guided exclusively in a plane extending in said machine running direction and perpendicular to the material web.
 4. The machine of claim 1, wherein a position of said rope nip is changeable in said machine running direction.
 5. The machine of claim 1, wherein said two ropes are guideable for a first positioning of said rope nip in said threading position and into a region of a web scanning device, said two ropes being retractable to a second positioning for a release of said device.
 6. The machine of claim 5, wherein said web scanning device includes a frame, and said two ropes are guideable through said frame.
 7. The machine of claim 5, wherein said web scanning device includes a frame, and said rope nip is adjustable between said threading position in which said two ropes are guided through said frame of said web scanning device and a retracted position in which said web scanning device is released.
 8. The machine of claim 1, wherein said rope guide includes a front guide section disposed in front of a web scanning device as viewed in said machine running direction, a rear guide section disposed after said web scanning device as viewed in said machine running direction, said two ropes are guided mutually separated between said front guide section and said rear guide section and on mutually opposite sides of said web scanning device, the material web including a material web tip, said rope nip is formed at the start of said rear guide section and is adjustable into a takeover position to take over said material web tip from said front guide section through a frame of a web scanning device and returning to a retracted position disposed behind said web scanning device, as viewed in the machine running direction, to transfer the material web into said rear guide section.
 9. The machine of claim 1, further comprising two sheaves and an adjustment device for positioning said two sheaves to form a rope nip, and wherein said two ropes are guided over said two sheaves.
 10. The machine of claim 1, further comprising a dryer section, and wherein said rope guide is provided for a threading of the marginal web strip into a said dryer section. 